The importance of fish oils in pregnancy is becoming more and more established, but we don’t always spend a lot of time talking about the importance of the placenta.
Fish oil is high in omega-3 fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These polyunsaturated fats are much sought after in nutrition and supplements since our human bodies cannot make these ingredients. Health Canada recommends at least 150 grams (5 ounces) of low mercury fish per week for all women of childbearing age .
So what does that have to do with the placenta? Let’s take a closer look.
The placenta is a temporary organ created during the first trimester of pregnancy. While the baby is growing, the placenta serves as the baby’s lungs, digestive tract, kidneys, and liver . Unsurprisingly, the placenta is complex in structure and is made up of specialized tissues needed to support these functions. Some people might think that the placenta develops as soon as the child is conceived. While this is partially true, it takes 8 to 12 weeks for the placenta to fully grow around the baby and become established. Several ingredients are needed for placental growth, including omega-3s .
Although omega-3s are essential for the structure and permeability of the membranes of all cells in the body, they are also essential for the formation of new blood vessels created in the placenta. Any disturbances in creating these blood vessels can cause less available blood flow and decreased function of the placenta, causing the inadequate blood supply to the baby. This can negatively affect the overall growth and development of the baby, as well as contribute to high blood pressure complications in the mother, gestational diabetes mellitus, fetal growth restrictions, and miscarriage .
The placenta connects the mother and the baby’s blood supply, sharing nutrients and oxygen, controlling temperature, and managing waste . Within these duties, the placenta is responsible for providing the fetus with fatty acids needed for ongoing growth and development. It has been suggested that the placenta favours long-chain polyunsaturated fatty acid, especially omega-3s, to deliver to the developing fetus. However, it is important to note that the amount of omega 3’s delivered to the baby is directly linked to the amount of omega-3s in the mother’s diet .
The placenta acts as a sort of gatekeeper between the mother and the fetus, allowing it to sense nutrient levels in both mother and fetus. Depending on the supply and demand of nutrients, the placenta can alter its function to match the growth of the fetus. In other words, it will decide how fast, how much, and how often the fetus receives nutrients . For example, in the third trimester, the fetal demands for DHA greatly increase to support the fast growth and development of the baby’s brain and visual system. The placenta is responsible for the timely delivery of this desired ingredient. If anything goes wrong with this delivery, difficulties may arise in the pregnancy, such as gestational diabetes mellitus and intrauterine growth restriction . In this way, the placenta regulates the rate of growth of the fetus depending on the nutrients available from the mother’s nutritional intake .
The body has internal anti-inflammatory mechanisms, and a controlled level of inflammation is a normal aspect of the pregnancy process. It is suggested that inflammation helps with the delivery of glucose to the fetus. Additionally, low levels of inflammation may help prevent the mother’s immune system from reacting to the differences in the baby’s DNA. That being said, an excess of inflammation in the placenta can also lead to the aforementioned dysfunctions including preeclampsia, intrauterine growth restriction, gestational diabetes mellitus, and miscarriage .
While we touched on the importance of omega-3s in creating the blood vessels in the placenta, and the delivery of omega-3s to the fetus, omega-3s are also known for their antioxidant and anti-inflammatory features. These features may be beneficial should levels of inflammation exceed the anti-inflammatory abilities of the body .
Additionally, inflammatory molecules called prostaglandins are involved in the onset of labour. It is theorized that the anti-inflammatory properties of omega-3s may help prevent premature labour by prolonging the length of pregnancy .
A healthy placenta is essential for a healthy pregnancy, and ultimately, for a healthy child. There appear to be several potential benefits of including omega-3 fatty acids in your nutritional plan. However, the role of omega-3s in placental health and development are still being studied. Although we have several theories about the mechanisms at work, further studies are needed to clarify the appropriate doses, timing, and desired health outcomes. The optimal dose of dietary or supplemented fish oil will likely depend on your individual case, so talk to your doctor or naturopathic doctor to create the right plan for you.
1. Canada, H. (2020). Prenatal Nutrition Guidelines for Health Professionals - Fish and Omega-3 Fatty Acids - Canada.ca, retrieved from https://www.canada.ca/en/health- canada/services/publications/food-nutrition/prenatal-nutrition-guidelines-health- professionals-fish-omega-3-fatty-acids-2009.html.
2. Burton, G., & Jauniaux, E. (2015). What is the placenta?. American Journal Of Obstetrics And Gynecology, 213(4), S6.e1-S6.e4. https://doi.org/10.1016/j.ajog.2015.07.050
3. Duttaroy, A., & Basak, S. (2020). Maternal dietary fatty acids and their roles in human placental development. Prostaglandins, Leukotrienes And Essential Fatty Acids, 155, 102080. https://doi.org/10.1016/j.plefa.2020.102080
4. Jones, M., Mark, P., & Waddell, B. (2014). Maternal dietary omega-3 fatty acids and placental function. REPRODUCTION, 147(5), R143-R152. https://doi.org/10.1530/rep- 13-0376
5. Gaccioli, F., Lager, S., Powell, T., & Jansson, T. (2012). Placental transport in response to altered maternal nutrition. Journal Of Developmental Origins Of Health And Disease, 4(2), 101-115. https://doi.org/10.1017/s2040174412000529
6. Leghi, G., & Muhlhausler, B. (2016). The effect of n-3 LCPUFA supplementation on oxidative stress and inflammation in the placenta and maternal plasma during pregnancy. Prostaglandins, Leukotrienes And Essential Fatty Acids, 113, 33-39. https://doi.org/10.1016/j.plefa.2016.08.010